406 
Isinglass, 
copied. After describing the fish, he says, as to the 
manner of making the isinglass, the sinewy parts of the 
fish are boiled in water till all of them be dissolved that will 
dissolve, then the gluey liquor is strained and set to cool. 
Being cold, the fat is carefully taken off, and the liquor 
itself is boiled to a juicy consistency, then cut to pieces 
and made into a twist, bent in form of a crescent, as com- 
monly sold, then hung upon a string and carefully dried. 
From this account it might rationally be concluded that 
every species of fish, which contained gelatinous princl= 
pies, would yield isinglass ; and this parity of reasoning 
seems to have given rise to the hasty conclusion of those 
who strenuously search for the extraction of isinglass from 
sturgeon, but as that fish is easily procurable, the ne- 
gligence of ascertaining the fact, by experiment, seems 
inexcusable. In my first attempt to discover the consti- 
tuent parts and manufacture of isinglass, relying too much 
upon the authority of some chemical authors, whose ve- 
racity I had experienced in many instances, I found my- 
self constantly disappointed. Glue, not Isinglass, was the 
result of every process ; and although in the same view, a 
journey to Russia proved fruitless, yet a steady persever- 
ance in the research proved not only successful as to this 
object, but in the pursuit to discover, resinous matter 
plentifully procurable in the British fisheries, which has 
been found by ample experience to answer similar pur- 
poses. It is now no longer a secret that our lakes and 
rivers of North America are stocked with immense quan- 
tities of fish, said to be of the same species with those in 
Muscovy, and yielding the finest isinglass ; the fisheries 
whereof, under due encouragement, would doubtless sup- 
ply all Europe with this valuable article. 
No artificial heat is necessary to the production of 
isinglass ; neither is the matter dissolved for this purpose, 
for as the continuity of its fibres would be destroyed by 
